1. Field of the Invention
The present invention relates to a technique for a heat dissipating substrate for elements.
2. Description of the Related Art
Thus far, development of power modules such as IGBTs (Insulated Gate Bipolar Transistor) etc., has been being advanced. Such a power module leads to a very large amount of heat generation due to the high voltage applied to the power module. Thus, in order to improve heat dissipation, a configuration in which such a power module is mounted on a metal substrate is employed. As such a metal substrate, an aluminum alloy substrate is becoming popular because it provides an advantage of light weight and an advantage of high heat conductivity.
With such an arrangement, there is a demand for a technique for adhering a resin substrate to an aluminum substrate with high bonding strength. Thus, it has been proposed that, by forming a high-quality oxide film on an aluminum substrate for mounting a printed circuit with high precision, such an aluminum substrate for mounting a printed circuit provides improved adhesion to a resin insulating member.